From UPSC perspective, the following things are important :
Prelims level : Aerosols
Mains level : Role of aerosols in maintaining Earth temperature
- Small aerosol particles help in “brightening” of clouds, enabling them to alter Earth’s radiative balance and ultimately its climate, according to a study.
What is Aerosol?
- An aerosol is a suspension of fine solid particles or liquid droplets, in air or another gas.
- Aerosols can be natural or anthropogenic. Examples of natural aerosols are fog, dust, forest exudates and geyser steam.
- Examples of anthropogenic aerosols are haze, particulate air pollutants and smoke.
Formation in atmosphere
- When deep, convective clouds in the tropics carry gases high into the atmosphere, they form small aerosol particles in a process called gas-to-particle conversion.
- As they condense, they grow big enough to brighten lower-level cloud in the lower troposphere.
- This gas-to-particle conversion brightens clouds in the tropics over both the Pacific and Atlantic Oceans.
Why are they significant?
- These brighter clouds reflect more energy from the sun back to space.
- Further, this formation of new particle covers about 40 per cent of the Earth’s surface, which means some of the current climate models underestimate the cooling impact of some clouds.
- Understanding how these particles form and contribute to cloud properties in the tropics will help us better represent clouds in climate models and improve those models.
- The study showed that in remote places with cleaner air, the effect of aerosol particle formation on clouds was found to be much larger,